// 阻塞队列的实现
#pragma once

#include <iostream>
#include <string>
#include <queue>
#include <pthread.h>

const int defaultcap=5;

template<typename T>
class BlockQueue
{
private:
    bool IsFull(){return _q.size()>=_cap;}
    bool IsEmpty(){return _q.empty();}

public:
    BlockQueue(int cap=defaultcap)
    :_cap(cap),_csleep_num(0),_psleep_num(0)
    {
        pthread_mutex_init(&_mutex,nullptr);
        pthread_cond_init(&_full_cond,nullptr);
        pthread_cond_init(&_empty_cond,nullptr);
    }

    void Equeue(const T& in)
    {
        pthread_mutex_lock(&_mutex);
        while(IsFull())//为什么要循环判断，因为线程可能被伪唤醒,如果是if判断就会直接执行_q.push(in)，但是是伪唤醒，队列可能还是没有空间
        {
            _psleep_num++;
             std::cout << "生产者，进入休眠了: _psleep_num" <<  _psleep_num << std::endl;
             pthread_cond_wait(&_full_cond, &_mutex);//在条件变量下等待，释放锁！！
             //运行到这里，说明被唤醒且申请锁成功
             _psleep_num--;
        }
        //运行到这里队列必有空间
        _q.push(in);
        //接下来要试着唤醒消费者
        if(_csleep_num>0)
        {
            pthread_cond_signal(&_empty_cond);
            std::cout << "唤醒消费者..." << std::endl;
        }
         pthread_mutex_unlock(&_mutex); //释放锁
    }

    T Pop()
    {
        // 消费者调用
        pthread_mutex_lock(&_mutex);
        while (IsEmpty())
        {
            _csleep_num++;
            pthread_cond_wait(&_empty_cond, &_mutex);
            _csleep_num--;
        }
        T data = _q.front();
        _q.pop();

        if (_psleep_num > 0)
        {
            pthread_cond_signal(&_full_cond);
            std::cout << "唤醒消费者" << std::endl;
        }

        // pthread_cond_signal(&_full_cond);
        pthread_mutex_unlock(&_mutex);
        return data;
    }
     ~BlockQueue()
    {
        pthread_mutex_destroy(&_mutex);
        pthread_cond_destroy(&_full_cond);
        pthread_cond_destroy(&_empty_cond);
    }

private:
    std::queue<T> _q;//临界资源！！
    int _cap; //容量大小
    pthread_mutex_t _mutex;
    pthread_cond_t _full_cond;
    pthread_cond_t _empty_cond;

    int _csleep_num;//消费者休眠的个数
    int _psleep_num;//生产者休眠的个数
};